Strike Industries FSA Single Folder Stock (1913)

The Strike Industries FSA Single Folder Stock is the SBR variant of the FSA Single Folder. Steel hinge, SI high-strength polymer end pieces, and a universal 1913 mount, identical to the brace version, with a rifle buttplate replacing the soft cuff. The mount accepts any 1913 Picatinny rear interface: Springfield Kuna, Sig MPX/MCX, Stribog with factory adapter, Scorpion with HBI 1913 adapter, and AR pistols with a 1913 endplate.

Total weight is 11 ounces and the stock folds left for compact transport. The hinge locks in both extended and folded positions. This is the same chassis Springfield ships as the factory FSA option on the Kuna KN9069B-FSA, just as a stock rather than a brace, so behavior under recoil and lockup are well-documented.

Pick this over the Magpul UCS when you want the lightest 1913 folding stock available with no LOP adjustment, and pick the Magpul UCS instead when you need a cheek riser or LOP range. The Single Folder Stock is the cheapest entry into the universal 1913 stock category at full build quality.